Validating Clinical Threshold Values for a Dashboard View of the Compensatory Reserve Measurement for Hemorrhage Detection

Victor A Convertino, Mallory R Wampler, Michael Johnson, Abdul Alarhayem, Tuan D Le, Susannah Nicholson, John G Myers, Kevin K Chung, Katie R Struck, Camaren Cuenca, Brian J Eastridge

J Trauma Acute Care Surg 2020 Jan 15;Epub ahead of print

Abstract

Background: Compensatory Reserve Measurement (CRM) is a novel noninvasive monitoring technology designed to assess physiologic reserve using feature interrogation of arterial pulse waveforms. This study was conducted to validate clinically relevant CRM values with a simplified color-coded dashboard view.

Methods: We performed a prospective observational study of 300 injured patients admitted to a level I trauma center. CRM was recorded upon ER admission. Data collected to complement the analysis included Patient demographics, vital signs, life-saving interventions (LSI), injury severity score (ISS) and outcomes were recorded. Threshold values of CRM were analyzed for predictive capability of hemorrhage.

Results: 285 patients met inclusion criteria. Mean age of the population was 47 years and 67% were male. Hemorrhage was present in 32 (11%) and LSI was performed in 40 (14%) patients. Transfusion of packed red blood cells (PRBC) was administered in 33 (11.6%) patients, and 21 (7.4%) were taken to the operating room for surgical or endovascular control of hemorrhage.

Statistical analyses were performed to identify optimal threshold values for 3 zones of CRM to predict hemorrhage. Optimal levels for red, yellow, and green areas of the dashboard view were stratified as follows: red if CRM<30%, yellow if CRM=30-59%, and green if CRM≥60%. Odds of hemorrhage increased by 12-fold (OR, 12.2; 95%CI, 3.8-38.9) with CRM<30% (red) and 6.5- fold (OR, 6.5; 95%CI, 2.7-15.9) with CRM=30-59% (yellow) when compared to patients with CRM≥60%. ROCAUC for 3-zone CRM was similar to that of continuous CRM (0.77 vs. 0.79), but further increased the ability to predict hemorrhage after adjusting for ISS (ROCAUC = 0.87).

Conclusion: A 3-zone CRM could be a potentially useful predictor of hemorrhage in trauma patients with added capabilities of continuous monitoring and a real-time ISS assessment. These data substantiate easily interpretable threshold dashboard values for triage with potential to improve injury outcomes.

Level of evidence: Diagnostic, Level II.